Carrier lifetime measurements in long-wave infrared InAs/GaSb superlattices under low excitation conditions

Abstract

Minority carrier lifetime in long-wave infrared (LWIR) type II InAs/GaSb superlattices was studied using the optical modulation response (OMR) technique in wide ranges of excitation and temperature. The measured carrier lifetime was found to increase superexponentially with decreasing excitation power density below the level of 1 mW/cm2 to 2 mW/cm2. The phenomenon was qualitatively explained by the presence of shallow trapping centers. © 2012 TMS.